CVE-2020-13936: Velocity Sandbox Bypass

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 22.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-10 · updated 2026-06-17

Description

An attacker that is able to modify Velocity templates may execute arbitrary Java code or run arbitrary system commands with the same privileges as the account running the Servlet container. This applies to applications that allow untrusted users to upload/modify velocity templates running Apache Velocity Engine versions up to 2.2.

Affected products

Apache Velocity Engine: before 2.3 — fixed in 2.3
Apache Software Foundation Apache WSS4J: 2.3.1
Debian Linux: 9.0
Oracle Banking Deposits And Lines Of Credit Servicing: 2.12.0
Oracle Banking Enterprise Default Management: from 2.3.0 through 2.4.1; 2.6.2, 2.7.1, 2.10.0, 2.12.0
Oracle Banking Loans Servicing: 2.12.0
Oracle Banking Party Management: 2.7.0
Oracle Banking Platform: from 2.3.0 through 2.4.1; 2.6.2, 2.7.1
Oracle Communications Cloud Native Core Policy: 1.14.0
Oracle Communications Network Integrity: 7.3.6
Oracle Hospitality Token Proxy Service: 19.2
Oracle Corporation Oracle Retail Integration Bus: 19.0.1
Oracle Retail Order Broker: 16.0
Oracle Retail Service Backbone: 19.0.1
Oracle Retail Xstore Office Cloud Service: 16.0.6, 17.0.4, 18.0.3, 19.0.2, 20.0.1
Oracle Utilities Testing Accelerator: 6.0.0.1.1, 6.0.0.2.2, 6.0.0.3.1

How to fix

Upgrade to a fixed version: Apache Velocity Engine 2.3. Check the vendor advisory for mitigations.

References

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